Clinical characteristics and treatment outcome for nonvestibular schwannomas of the head and neck

Studies involving head and neck schwannomas have focused predominantly on involvement of the vestibulocochlear nerve complex (acoustic neuroma) because of the associated morbidity related to lesions involving that region. However, the majority of head and neck schwannomas are not of vestibular nerve origin and may also produce significant morbidity due to involvement of the orbit, skull base, and cranial nerves. The purpose of this study is to examine the presenting signs and symptoms, location, nerve of origin, and outcome after treatment of patients with nonvestibular schwannomas of the head and neck. The medical and pathological records of all patients with nonvestibular head and neck schwannomas treated at a single institution between 1979 and 1999 were retrospectively reviewed. Eighteen (69%) of 26 patients presented with symptoms secondary to mass effect or nerve deficit. The parapharyngeal space was the most common site of tumor origin occurring in 8 patients (31%). The nerve of origin was identified in 16 patients (62%). Twenty-three patients (88%) had complete surgical excision, and 3 patients (12%) had subtotal resection. Postoperative nerve injury occurred in 16 patients (62%) with resolution in 7 patients (44%). Nonvestibular head and neck schwannomas occur most commonly in the parapharyngeal space, and presenting signs or symptoms are usually related to mass effect or neural deficit. Complete tumor removal is often achieved, but subtotal or near-total resection may be indicated for patients with extensive skull base, middle ear, or facial nerve involvement. Postoperative morbidity is associated with nerve injury from the surgical approach and/or resection of the involved nerve.